1. Field of the Invention
This invention pertains to self-propelled upright vacuum cleaners. More specifically, this invention pertains to a novel transmission neutral locking structure for automatically placing and locking the transmission on a self-propelled upright vacuum cleaner in its neutral position when the handle or bag housing portion of the cleaner is placed in its upright storage position.
This invention also pertains to an upright vacuum cleaner having a structure for automatically engaging and rotating the agitator when the bag housing is located in a generally inclined operating position and automatically disengaging and stopping rotation of the agitator when the bag housing is located in the upright storage position, which structure may also be manually actuated to maintain disengagement of the agitator for cleaning bare floors.
2. Description of Related Prior Art
It is known in the prior art to provide an upright vacuum cleaner with a transmission in the foot or lower floor engaging portion of the cleaner and a transmission actuator member mounted to the foot adjacent to the transmission. A Bowden cable typically extends from the actuator on the foot to a hand grip that is reciprocally mounted for rectilinear motion to the top of the bag housing or handle portion of the cleaner. In order to prevent accidental engagement of the transmission when the bag housing is in the upright storage position, it is also known to provide a member on the lower end of the bag housing or handle portion of the vacuum cleaner that will engage the transmission actuator, or actuate a member on the foot that engages the transmission actuator, and thereby place and lock the transmission actuator in its neutral position. Thus, if an operator were to accidentally bump the hand grip while the cleaner's bag housing is in the upright storage position and the motor is running, the transmission is prevented from being engaged and the cleaner is prevented from accidentally propelling itself across the floor and causing an accident. Such transmission neutral locking arrangements for self-propelled upright vacuum cleaners are disclosed in U.S. Pat. Nos. 4,766,640; 4,347,643 and 4,249,281.
It is also known to place the transmission actuator on the lower end of the bag housing such that the actuator engages and actuates the transmission when the bag housing is in its inclined operating position and does not engage the transmission when the bag housing is in its upright storage position. When the transmission is not being engaged by the actuator, the transmission is self-biased into an idling neutral position. An example of this type of self-propelled vacuum cleaner can be found in U.S. Pat. No. 3,618,687.
As disclosed in commonly owned U.S. Pat. No. 5,537,712, the disclosure of which is hereby incorporated herein as of reference, it is known to engage an agitator by pressing an idler pulley on a pivotal idler arm against the agitator drive belt, thereby placing the agitator drive belt under tension and transferring power to the agitator. It is also known to automatically engage and disengage the agitator as the handle portion of the cleaner is raised and lowered by providing a protrusion or cam on the bag housing that contacts and pivots the idler arm to lift the idler pulley out of engagement with the agitator drive belt. The U.S. Pat. No. 5,537,712 patent does not, however, disclose a means for shutting the agitator off for cleaning bare floors.